JP5761342B2 - Implant keeper and assembly thereof, and method of fixing keeper - Google Patents

Description

  The present invention relates to an implant keeper for fixing a magnetic attachment for dentures to an implant body, an assembly thereof, and a keeper fixing method.

  In recent years, in dental implant treatment, a method of fixing a keeper made of a soft magnetic material to an implant body embedded in a jawbone and magnetizing a denture attachment with a built-in magnet on the implant body so that the denture can be easily attached and detached. ing.

  US Pat. No. 6,709,270 discloses a magnetic dental attachment in which a denture attachment 105 containing a magnet 155 is magnetically attached to a keeper 103 made of a soft magnetic material screwed into an implant body 110, as shown in FIG. doing. The keeper 103 includes a conical tapered portion 135 provided at the upper portion, and a ring portion 137 that protrudes from the outer peripheral surface at the upper end of the conical tapered portion 135 and has an annular groove on the back side. The implant body 110 has a conical tapered recess 115 complementary to the tapered portion 135 of the keeper 103. When the keeper 103 is screwed into the implant body 110, the distal end portion of the ring portion 137 of the keeper 103 and the upper end portion of the implant body 110 are brought into contact with each other, and the distal end portion of the ring portion 137 is elastically deformed in the radial direction. The tension generated by this elastic deformation prevents the keeper 103 from loosening. However, in the denture attachment of US Pat. No. 6,709,270, since the contact area between the tip of the ring part 137 and the upper end of the implant body 110 is small, the tension decreases due to plastic deformation of the ring part 137 when used for a long time, and the keeper There is a fear of 110 slack.

  JP-A-2009-131620, as shown in FIG. 16, (a) an implant body 205, (b) an abutment 204 having a head 241 having a female thread portion 243 and screwed into the implant body 205, (c) a keeper body 202 made of a soft magnetic material having a recess 221 for receiving the head 241 of the abutment 204, and a female thread portion 222 provided along the central axis so as to communicate with the recess 221; ) The keeper body 202 includes a female screw portion 222 and a screw member 203 that is screwed to the female screw portion 243 of the abutment 204. After the keeper main body 202 is screwed to the abutment 204 screwed to the implant main body 205, the screw member 203 An implant keeper assembly is disclosed in which a female screw portion 222 of a keeper body 202 and a female screw portion 243 of an abutment 204 are screwed together. However, since the screw member 203 does not have a portion that contacts the keeper main body 202 or the abutment 204, it is necessary to manually adjust the axial position of the screw member 203 screwed to the keeper main body 202 and the abutment 204.

  In addition, since the head of the keeper body 202 is very thin, about 1 mm, the thread of the female thread portion 222 of the keeper body 202 is the minimum number necessary for screwing with the screw member 203 (about 3 to 4 pieces) Only. Therefore, when the screwing position of the screw member 203 is shifted to the abutment 204 side, the coupling strength between the keeper main body 202 and the screw member 203 becomes insufficient, and when the screw member 203 is shifted to the opposite side, the head of the screw member 203 is moved to the keeper main body 202. Therefore, the screw member 203 must be accurately positioned by hand.

  Accordingly, an object of the present invention is to provide an implant keeper that can be accurately and easily screwed onto an abutment and does not loosen even when used for a long period of time.

  Another object of the present invention is to provide a method of fixing the above-described implant keeper to an abutment.

  Still another object of the present invention is to provide an implant keeper assembly comprising a keeper body, an abutment, and a screw member for screwing them together.

  The keeper for an implant of the present invention is provided with (a) a recess for receiving the head of an abutment having a female thread portion, and a central axis so as to communicate with the concave portion, and is larger than the female thread portion of the abutment. A keeper main body made of a soft magnetic material having a female thread portion having a nominal diameter, (b) a small-diameter screw portion that is screwed with the female screw portion of the abutment, and a large-diameter screw portion that is screwed with the female screw portion of the keeper body A two-stage screw member, and the small-diameter screw portion is screwed into the female screw portion of the abutment, and the large-diameter screw portion is screwed into the female screw portion of the keeper body, and then the keeper When the main body is rotated in the screwing direction, the keeper main body is firmly fastened to the abutment by the two-stage screw member.

  The method for fixing the implant keeper to the abutment according to the present invention includes screwing the small-diameter screw portion of the two-stage screw member into the female screw portion of the abutment and the two-stage screw to the female screw portion of the keeper body. After the large-diameter screw portion of the member is screwed, the keeper main body is rotated in the screwing direction, and the keeper main body is firmly fastened to the abutment by the two-stage screw member.

  The two-stage screw member has a stepped portion or a tapered portion between the small-diameter screw portion and the large-diameter screw portion, and the two-stage screw member until the stepped portion or the tapered portion engages with the upper end surface of the abutment. When the stepped screw member is screwed into the female threaded portion of the abutment, it is preferable that the two-stage screw member can be accurately positioned in the axial direction.

  An implant keeper assembly of the present invention to be fixed to an implant body embedded in a jawbone includes: (a) a head, a female screw provided along a central axis of the head, and a lower part of the head. An abutment having a male screw portion screwed into the implant body; (b) a recess for receiving the head of the abutment; provided along the central axis so as to communicate with the recess; A keeper body made of a soft magnetic material having a female thread part having a larger nominal diameter than the female thread part of the abutment; (c) a small-diameter thread part screwed into the female thread part of the abutment; and a female thread part of the keeper body; A two-stage screw member having a large-diameter screw portion to be screwed, and screwing the small-diameter screw portion of the two-stage screw member into the female screw portion of the abutment, After the large-diameter screw portion of the two-stage screw member is screwed into the screw portion, when the keeper main body is rotated in the screwing direction, the keeper main body is firmly fastened to the abutment by the two-stage screw member. It is characterized by being worn.

  In the implant keeper and the assembly thereof, the two-stage screw member has a stepped portion or a tapered portion between the small-diameter screw portion and the large-diameter screw portion, and the stepped portion or the tapered portion is the abutment. It is preferable that the two-stage screw member can be accurately positioned in the axial direction when the two-stage screw member is screwed into the female thread portion of the abutment until the upper end surface of the abutment is engaged.

  At least a part of the head of the abutment has a truncated cone shape, and the inner surface of the concave portion of the keeper body has a conical shape complementary to the truncated cone portion of the abutment head, thereby It is preferable that the frustoconical portion of the abutment head is in close contact with the inner surface of the concave portion of the keeper body when fastened to the abutment.

  It is preferable that at least a part of the side surface portion of the keeper main body has a nut shape, and the keeper main body is rotated in the screwing direction by using a tool that engages with the nut-shaped side surface portion.

  The abutment has a flange portion extending radially outward from a lower end of the head, an upper surface outer peripheral portion of the flange portion abuts an outer edge portion of the keeper body, and a lower surface of the flange portion is the implant. It is preferable to contact the upper end surface of the main body.

  The head of the abutment is inclined with respect to the central axis of the implant body, and the abutment is inserted into a central hole of the implant body, and the side surface of the head from the cylindrical portion. It is preferable that the abutment is fixed to the implant body by screwing a screw member penetrating the through hole and the cylindrical portion into the female screw portion of the implant body.

  In the present invention, since a two-stage screw member having a large-diameter screw portion and a small-diameter screw portion is used, the large-diameter screw portion screwed into the female screw portion of the keeper body made of a soft magnetic material and the female screw portion of the abutment are screwed together. A tension is applied in the opposite direction to the small-diameter screw portion, and the keeper main body and the abutment are firmly fastened by a two-stage screw member, and they do not loosen even when used for a long time. Further, since the two-stage screw member has a stepped portion or a tapered portion between the small-diameter screw portion and the large-diameter screw portion, when the two-stage screw member is screwed to the female screw portion of the abutment, the stepped portion or the tapered portion is formed. By engaging with the upper end surface of the abutment, the two-stage screw member can be accurately and easily positioned in the axial direction (displacement of the screwing position can be prevented).

  Since the keeper for an implant of the present invention has a small number of parts and can be easily attached to an abutment, a dental implant can be treated in a short time.

It is an exploded sectional view showing the keeper assembly for implants by a first embodiment of the present invention. FIG. 2 is a partial cross-sectional view showing the implant keeper assembly of FIG. It is a perspective view which shows the keeper for implants by 1st embodiment of this invention. FIG. 4 is a partial cross-sectional perspective view showing the implant keeper of FIG. It is sectional drawing which shows the keeper main body used for 1st embodiment of this invention. FIG. 4 is a partial sectional view showing a state in which the implant keeper of FIG. 3 is screwed to an abutment. FIG. 2 is a partial cross-sectional view showing a state where a magnetic attachment is attracted to the implant keeper assembly of FIG. It is a disassembled sectional view which shows the keeper assembly for implants by 2nd embodiment of this invention. FIG. 9 is a partial cross-sectional view showing the implant keeper assembly of FIG. It is an expanded partial sectional view which shows the state which fixed the keeper for implants by 2nd embodiment of this invention to the abutment. It is a top view which shows the two-stage screw member used for 2nd embodiment of this invention. FIG. 12 is a partial cross-sectional view showing the two-stage screw member of FIG. 11 (a). It is a fragmentary sectional view which shows the state just before screwing a two-stage type screw member to an abutment in order to screw the keeper for implants by 2nd embodiment of this invention to an abutment. It is a fragmentary sectional view showing signs that a two-stage type screw member is screwed together with an abutment. It is a fragmentary sectional view which shows the state which covered the keeper main body on the two-stage type screw member screwed together to the abutment. It is a fragmentary sectional view showing signs that the two-stage type screw member screwed into the abutment is screwed into the keeper body. It is a fragmentary sectional view which shows a mode that a keeper main body is rotated in a screwing direction, after a two-stage type screw member screws together with an abutment and a keeper main body. It is a fragmentary sectional view which shows the state by which the keeper main body was firmly fastened by the abutment with the two-stage type screw member. It is a disassembled sectional view which shows the keeper assembly for implants by 3rd embodiment of this invention. FIG. 14 is a partial cross-sectional view showing the implant keeper assembly of FIG. FIG. 6 is an exploded cross-sectional view showing a magnetic dental attachment described in US Pat. No. 6,709,270. 1 is a cross-sectional view showing an implant keeper assembly described in JP-A-2009-131620.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings, but the description of one embodiment is applicable to other embodiments unless otherwise specified. The illustrated example is not limited, and various modifications can be made within the scope of the idea of the present invention.

[1] First embodiment
(a) Structure FIGS. 1 and 2 show an implant keeper and its assembly according to a first embodiment of the present invention. The implant keeper assembly fixed to the implant body 5 includes an abutment 4 screwed into the implant body 5 and a keeper 1. The keeper 1 includes a keeper body 2 having a screw hole 22, and a keeper body 2. And the two-stage screw member 3 screwed into the screw hole 45 of the head 41 of the abutment 4.

  The implant body 5 is a cylindrical member having a male threaded portion 53 on the outer peripheral surface for embedding in the jawbone, a central hole 51 for inserting the lower male threaded portion 43 of the abutment 4, and the back side of the central hole 51 A female screw portion 52 that is screwed with the male screw portion 43, and an annular convex portion 54 that protrudes concentrically with the central hole portion 51 from the upper end surface. The implant body 5 preferably has an outer diameter (about 3 to 6.5 mm) and a length (about 10 mm) according to normal implant treatment. The implant body 5 is preferably made of pure titanium or a titanium alloy from the viewpoint of biocompatibility with the jawbone, corrosion resistance, and mechanical strength. In order to improve biocompatibility, surface treatment with hydroxyapatite may be performed.

  The abutment 4 is screwed to a head 41 that engages with the tapered recess 21 of the keeper 1, a flange 42 that extends radially outward from the lower end of the head 41, and a female thread 52 of the implant body 5. And a lower male screw portion 43. The flange portion 42 has two upper surfaces, and the bottom edge portion 25 of the keeper main body 2 abuts on the outer lower upper surface portion 42a. Further, the lower surface 42b of the flange portion 42 is in contact with the upper end surface of the implant body 5, and the annular recess 42c with which the annular projection 54 of the implant body 5 is engaged is provided on the lower surface 42b. The head portion 41 of the abutment 4 has a female thread portion 45 that opens to the center of the upper end surface, and a nut-shaped side surface portion 47, and a part of the side surface portion 47 engages with the tapered recess 21 of the keeper 1. 47a. The abutment 4 is preferably made of the same material as the implant body 5.

  As shown in FIGS. 1 to 6, the truncated cone-shaped keeper body 2 has a tapered recess 21 that receives the head 41 of the abutment 4, and a center of the upper surface 23 so as to communicate with the tapered recess 21. And an internal thread 22 that opens. The female threaded portion 22 of the keeper body 2 has a larger nominal diameter than the female threaded portion 45 of the abutment 4. The keeper main body 2 (height t1) has a truncated cone shape (D1 <D2), and a part of the conical side surface 24 is an octagonal nut portion 24a having a height t3 that is about 1/2 of t1, for example. Of course, the octagonal nut shape is an example, and the hexagonal nut shape in which the interval between the opposing surfaces conforms to JIS B 1181 may be used. The size of the upper surface 23 of the keeper body 2 is appropriately set according to the size of the magnetic denture attachment 9 (see FIG. 7). Since the tapered concave portion 21 of the keeper body 2 is complementary to the tapered surface portion 47a of the head 41 of the abutment 4, the tapered concave portion 21 is closely engaged with the tapered surface portion 47a.

  In the two-stage screw member 3, a small-diameter screw portion 31 screwed into the female screw portion 45 of the abutment 4 and a large-diameter screw portion 32 screwed into the female screw portion 22 of the keeper main body 2 are connected coaxially and integrally. Thus, a stepped portion 33 is provided between the small-diameter screw portion 31 and the large-diameter screw portion 32. When the two-stage screw member 3 is screwed into the female thread portion 45 of the abutment 4, the step portion 33 of the two-stage screw member 3 is engaged with the upper end face 46 of the abutment 4, and the two-stage screw member 3 is axially moved. It functions as a locking part that accurately positions in the direction. The two-stage screw member 3 has a clover hole 34a for driver engagement on a flat upper end surface 34. Instead of the clover hole 34a, a slot specified in JIS B 1117 or a hexagon hole specified in JIS B 1177 may be used.

  The nominal diameter d1 of the small diameter screw portion 31 of the two-stage screw member 3 is preferably about 1.2 to 1.8 mm, and the nominal diameter d2 of the large diameter screw portion 32 is preferably about 1.6 to 3.0 mm. The nominal diameter d1 of the small-diameter screw portion 31 needs to be at least about 1.2 mm in order to function as a screw. Further, if the nominal diameter d2 of the large-diameter screw portion 32 is more than 3.0 mm, the area of the upper surface 23 of the keeper body 2 is reduced, and the attractive force to the magnetic denture attachment is weak. The stepped portion 33 of the two-stage screw member 3 needs to be large enough to be locked to the upper end surface when the two-stage screw member 3 is screwed to the abutment 4. The ratio d2 / d1 between the nominal diameter d2 of the large-diameter screw portion 32 and the nominal diameter d1 of the small-diameter screw portion 31 is preferably about 1.2 to 1.5.

  The keeper body 2 needs to be formed of a soft magnetic material so as to be magnetically attracted to the magnetic denture attachment, and ferritic stainless steel (see JIS G 4303) having excellent soft magnetism and corrosion resistance is preferable. The two-stage screw member 3 is also preferably made of a soft magnetic material like the keeper body 2 so that it can be magnetically attracted to the magnetic denture attachment, but it is made of a nonmagnetic material such as titanium because it is small. Also good.

(b) Fixing method In order to fix the implant keeper 1 to the abutment 4, first, the male screw portion 43 of the abutment 4 is screwed into the female screw portion 52 of the implant main body 5 embedded in the jawbone, and the implant main body 5 Abutment 4 is fixed to. Using a screwdriver that fits into the clover hole 34a, the small-diameter screw portion 31 of the two-stage screw member 3 is moved to the abutment 4 until the stepped portion 33 of the two-stage screw member 3 contacts the upper end surface 46 of the abutment 4. And screwed into the female thread part 45 of FIG. Next, the keeper main body 2 is put on the abutment 4, and the large-diameter screw portion 32 of the two-stage screw member 3 is screwed into the female screw portion 22 of the keeper main body 2. Until the bottom edge 25 of the keeper main body 2 abuts on the outer peripheral surface 42a of the upper surface of the flange portion 42 of the abutment 4 or until the tapered recess 21 of the keeper main body 2 abuts on the upper end surface 46 of the head 41 of the abutment 4 Then, the keeper body 2 is rotated in the screwing direction.

  In a state where the keeper body 2 and the abutment 4 are in contact with each other, the keeper body 2 is rotated in the screwing direction (usually the right-handed screw direction) with a predetermined wrench so that the keeper body 2 is firmly fastened to the abutment 4. At this time, the upper end surface 34 of the two-stage screw member 3 is prevented from protruding from the upper surface 23 of the keeper body 2. That is, the upper end surface 34 of the two-stage screw member 3 is substantially flush with or slightly lower than the upper surface 23 of the keeper body 2. Since the stepped portion 33 of the two-stage screw member 3 is brought into contact with the upper end surface 46 of the abutment 4 by screwing, the large-diameter screw portion 32 of the two-stage screw member 3 is the same as or slightly the same as the female screw portion 22 of the keeper body 2. By setting it short, the positioning of the upper end surface 34 of the two-stage screw member 3 can be performed accurately and easily. Further, the stepped portion 33 of the two-stage screw member 3 is locked to the upper end surface 46 of the abutment 4, so that the screwing position of the keeper body 2 to the two-stage screw member 3 is not shifted.

  As shown in FIGS. 2 and 6, the lower part of the thread of the large-diameter screw portion 32 of the two-stage screw member 3 is screwed into the two-stage screw member 3 of the keeper body 2 so that the female screw portion of the keeper body 2 The upper part of the screw thread 22 is pressed, and the upper part of the screw thread of the small diameter screw part 31 of the two-stage screw member 3 presses the lower part of the screw thread of the female screw part 45 of the abutment 4. That is, the keeper body 2 is pressed downward by the two-stage screw member 3, and the abutment 4 is pressed upward. Therefore, the keeper main body 2 is firmly fastened to the abutment 4 and does not loosen even when a repeated load is applied.

(c) Magnetic Attachment As shown in FIG. 7, the denture is fixed by magnetically attracting the denture magnetic attachment 9 to the upper surface 23 of the keeper body 2. The magnetic attachment 9 itself may be a known one (for example, see WO 2005/077297). A magnetic attachment 9 shown in FIG. 7 includes a cup-shaped yoke 91 made of a soft magnetic material having a recess having a circular cross section, a disk-shaped permanent magnet 92 housed in the recess and magnetized in the thickness direction, and the recess. It consists of a sealing plate 93 for sealing. The seal plate 93 is a member that seals the permanent magnet 92 in the recess and serves as a magnetic path, and includes a disc-shaped yoke 931 made of a soft magnetic material and a seal ring 932 made of a non-magnetic material fixed to the outer periphery thereof. It consists of The soft magnetic material is preferably a corrosion resistant metal such as ferritic stainless steel (for example, SUS447J1), and the nonmagnetic material is preferably a corrosion resistant metal such as austenitic stainless steel (for example, SUS316L).

  As the permanent magnet 92, an R—T—B based sintered magnet having high magnetic properties (for example, an Nd—Fe—B based anisotropic sintered magnet) is suitable. This sintered magnet has 27 to 34% by mass of R (at least one kind of rare earth element including Y, and must contain at least one of Nd, Dy, and Pr), 0.6 to 1.8% by mass of B, and the balance substantially In particular, it preferably has a composition consisting of T (Fe or Co). When R is less than 27% by mass, the coercive force (iHc) is too low, and when it exceeds 34% by mass, the residual magnetic flux density Br is significantly reduced. When B is less than 0.6% by mass, a coercive force that can withstand practical use cannot be obtained, and when it exceeds 1.8% by mass, Br is significantly reduced. The more preferred composition of the RTB sintered magnet is 27 to 32 mass% R, 0.6 to 1.8 mass% B, 0.0001 to 20 mass% Co, 0.001 to 3 mass% M (Al, Si, Cu, Ga). At least one selected from the group consisting of Nb, Mo and W), and the balance substantially consisting of Fe.

[2] Second embodiment
(a) Structure FIGS. 8 to 10 show an implant keeper and its assembly according to a second embodiment of the present invention. The second embodiment is basically the same as the first embodiment except that a two-stage screw member 6 shown in FIG. 11 is used as the screw member of the keeper body 2.

The two-stage screw member 6 includes a small-diameter screw portion 61 (length L ₁ ) screwed into the female screw portion 45 of the abutment 4 along the central axis in order from the bottom, and a non-threaded small-diameter portion 63 (length). L ₃ ) and a large-diameter screw portion 62 (length L ₂ ) that is screwed into the female screw portion 22 of the keeper body 2 are integrally provided. The small diameter portion 63 includes a first taper portion 63a that decreases in diameter from the large diameter screw portion 62 toward the small diameter screw portion 61, and a second taper portion 63b that decreases in diameter from the small diameter screw portion 61 toward the large diameter screw portion 62. Consists of. The upper end face 64 of the two-stage screw member 6 is provided with a clover hole 64a for screwing in a driver. Instead of the clover hole 64a, a slot specified in JIS B 1117 or a hexagon hole specified in JIS B 1177 may be used. The nominal diameters of the small-diameter screw portion 61 and the large-diameter screw portion 62 of the two-stage screw member 6 may be the same as those of the two-stage screw member 3.

(b) Fixing method In order to fix the keeper 1 to the abutment 4, as shown in FIG. 12 (a), the small-diameter screw portion 61 of the two-stage screw member 6 is abutted by the tool D fitted in the clover hole 64a. The two-stage screw member until the first taper portion 63a of the two-stage screw member 6 comes into contact with the upper end surface 46 of the abutment 4, as shown in FIG. Rotate 6 in the screwing direction. As a result, as shown in FIG. 12 (c), the upper part of the thread of the small-diameter screw part 61 of the two-stage screw member 6 presses the lower part of the thread of the female thread part 45 of the abutment 4, The screw member 6 is locked to the abutment 4. If the length of the female screw portion 22 of the keeper main body 2 and the length of the large-diameter screw portion 62 of the two-stage screw member 6 are set in advance, the abutment 4 of the first taper portion 63a of the two-stage screw member 6 is set. By contacting the upper end surface 46, the upper end surface 64 of the two-stage screw member 6 can be accurately and easily positioned. Further, since the two-stage screw member 6 is locked to the abutment 4 by the contact of the first tapered portion 63a of the two-stage screw member 6 with the upper end surface 46 of the abutment 4, the screwing of the keeper body 2 is prevented. At this time, the screwing position of the two-stage screw member 6 does not shift. Therefore, the first taper portion 63a can be called a locking portion.

  As shown in FIG. 12 (d), the keeper main body 2 is put on the abutment 4, and the female screw portion 22 of the keeper main body 2 is screwed with the large-diameter screw portion 62 of the two-stage screw member 6. Next, the keeper body 2 until the bottom edge 25 of the keeper body 2 abuts against the flange portion 42 of the abutment 4 or the tapered recess 21 of the keeper body 2 abuts the upper end surface 46 of the head 41 of the abutment 4 Is rotated in the screwing direction. As shown in FIG. 12 (e), the keeper body 2 is rotated in the screwing direction with a wrench 16 set to a predetermined torque (for example, 20 to 30 N · cm), and the keeper body 2 is moved by the two-stage screw member 6. Tighten firmly to the abutment 4. As described above, the female screw portion 22 of the keeper main body 2 and the large-diameter screw portion 62 of the two-stage screw member 6 are set to a predetermined length. It does not protrude from the upper surface 23 (substantially flush with or slightly lower than the upper surface 23 of the keeper body 2).

  By screwing the keeper body 2, as shown in FIGS. 10 and 12 (f), the lower part of the thread of the large diameter thread part 62 of the two-stage screw member 6 is above the thread of the female part 22 of the keeper body 2. The upper part of the thread of the small diameter thread part 61 of the two-stage screw member 6 presses the lower part of the thread of the female thread part 45 of the abutment 4. That is, the keeper body 2 is pressed downward by the two-stage screw member 6, and the abutment 4 is pressed upward. Therefore, the keeper main body 2 is firmly fastened to the abutment 4 and does not loosen even when a repeated load is applied.

  Instead of the procedure shown in FIGS. 12 (a) to 12 (d), the large-diameter screw portion 62 of the two-stage screw member 6 is screwed into the female screw portion 22 of the keeper body 2, and then the female screw of the abutment 4 is used. The small-diameter screw part 61 of the two-stage screw member 6 may be screwed into the part 45. At that time, when the two-stage screw member 6 is screwed to the female thread portion 45 of the abutment 4 until the first tapered portion 63a of the two-stage screw member 6 contacts the upper end surface 46 of the abutment 4, The two-stage screw member 6 engages with the abutment 4 in a state where the upper part of the thread of the small diameter screw part 61 of the screw member 6 presses the lower part of the thread of the female thread part 45 of the abutment 4. Further, after the keeper body 2 is covered with the abutment 4, the two-stage screw member 6 may be sequentially screwed into the female thread portion 22 of the keeper main body 2 and the female thread portion 45 of the abutment 4.

[3] Third Embodiment FIGS. 13 and 14 show an implant keeper and its assembly according to a third embodiment of the present invention. The implant keeper assembly includes an abutment 7 that is screwed to the implant body 5 using screws 8, and a keeper 1 that is fastened to the head 71 of the abutment 7. The keeper 1 includes a keeper body 2 and a two-stage screw member 6. The keeper 1 and the implant body 5 itself are the same as those in the second embodiment.

  The abutment 7 is coaxially connected to a head 71 that engages with the keeper body 2, a diameter-expanded portion 72 that is connected to the lower end of the head 71, and a through-hole 77 that extends through the head 71 to expand the abutment 7. And a cylindrical portion 73 protruding from the lower surface 72b of the diameter portion 72. The upper surface outer peripheral portion 72 a of the enlarged diameter portion 72 abuts on the bottom edge portion 25 of the keeper 1. The head 71 of the abutment 7 has a female thread 75 that opens to the upper end surface 76, and the small-diameter thread 61 of the two-stage screw member 6 is screwed into the female thread 75. Since the first taper portion 63a of the two-stage screw member 6 screwed into the female screw portion 75 contacts the upper end surface 76 of the head 71, the two-stage screw member 6 protruding from the head 71 of the abutment 7 is large. The upper end surface of the diameter screw portion 62 is substantially flush with or slightly lower than the upper surface 23 of the keeper body 2.

  Since the head 71 of the abutment 7 and its female screw portion 75 are inclined by an angle α with respect to the cylindrical portion 73 (through hole 77), the through hole 77 into which the screw 8 is inserted opens to the side surface of the head 71. ing. The angle α is preferably within a range of 15 to 35 °, and more preferably 15 to 30 °.

  After inserting the cylindrical portion 73 of the abutment 7 into the central hole portion 51 of the implant body 5, the screw member 8 is inserted into the through hole 77 of the abutment 7, and the male screw portion 81 of the screw member 8 is inserted into the female screw portion 52 of the implant body 5. The abutment 7 is fixed to the implant body 5 when screwed into the implant body 5. The method for screwing the keeper 1 to the abutment 7 is the same as in the second embodiment.

Claims (11)

(a) a recess for receiving the head of an abutment having an internal thread, and an internal thread that is provided along the central axis so as to communicate with the recess and has a larger nominal diameter than the internal thread of the abutment A two-stage screw member comprising: a keeper body made of a soft magnetic material having; a small-diameter screw portion screwed with the female screw portion of the abutment; and a large-diameter screw portion screwed with the female screw portion of the keeper main body. The two-stage screw member has a taper portion between the small-diameter screw portion and the large-diameter screw portion, the small-diameter screw portion is screwed into the female screw portion of the abutment, and the keeper After screwing the large-diameter screw portion into the female screw portion of the main body and rotating the keeper main body in the screwing direction, the keeper main body is firmly fastened to the abutment by the two-stage screw member , Taper Features There When screwing the two-stage screw member into the internal thread portion of the abutment until it engages the upper end surface of the abutment, the Rukoto can accurately position the two-stage screw member in the axial direction An implant keeper. 2. The keeper for an implant according to claim 1 , wherein at least a part of the head portion of the abutment has a truncated cone shape, and an inner surface of the concave portion of the keeper body is complementary to the truncated cone shape portion of the abutment head. An implant keeper characterized by having a conical shape so that when the keeper main body is fastened to the abutment, the frustoconical portion of the abutment head is in close contact with the inner surface of the concave portion of the keeper main body. 3. The keeper for an implant according to claim 1 , wherein at least a part of the side surface portion of the keeper main body is nut-shaped, and the keeper main body is screwed using a tool that engages with the nut-shaped side surface portion. Implant keeper characterized by being freely rotatable. An implant keeper assembly for fixing to an implant body embedded in a jawbone, comprising: (a) a head, a female screw provided along a central axis of the head, and extending below the head An abutment having a male thread portion screwed into the implant body, (b) a recess for receiving a head of the abutment, and a central axis so as to communicate with the recess, the abutment A keeper body made of a soft magnetic material having a female thread portion having a larger nominal diameter than the female thread portion of the mentment; (c) a small-diameter thread portion that is screwed with the female thread portion of the abutment; and the female thread portion and the screw of the keeper body. A two-stage screw member having a tapered portion formed between the small-diameter screw portion and the large-diameter screw portion, and the female screw portion of the abutment includes the two-stage screw member. Stepped screw When the small-diameter screw portion of the material is screwed together and the large-diameter screw portion of the two-stage screw member is screwed into the female screw portion of the keeper main body, the keeper main body is rotated in the screwing direction. The keeper main body is firmly fastened to the abutment by a screw-type screw member, and the two-stage screw member is screwed onto the female screw portion of the abutment until the tapered portion engages with the upper end surface of the abutment. is allowed when, implant keeper assembly, wherein Rukoto accurately position the two-stage screw member in the axial direction. 5. The implant keeper assembly according to claim 4 , wherein at least a part of the head portion of the abutment has a truncated cone shape, and an inner surface of the concave portion of the keeper body has a truncated cone shape portion of the abutment head portion. For implants, which have a complementary conical shape, so that when the keeper main body is fastened to the abutment, the frustoconical portion of the abutment head closely contacts the inner surface of the concave portion of the keeper main body. Keeper assembly. 6. The keeper assembly for an implant according to claim 4 , wherein at least a part of a side surface portion of the keeper main body is nut-shaped, and the keeper main body is screwed using a tool that engages with the nut-shaped side surface portion. An implant keeper assembly characterized by rotating in a direction. The keeper assembly for implants according to any one of claims 4 to 6 , wherein the abutment has a flange portion extending radially outward from a lower end of the head portion, and an upper surface outer peripheral portion of the flange portion is An implant keeper assembly, wherein the keeper body is in contact with an outer edge portion of the keeper body, and a lower surface of the flange portion is in contact with an upper end surface of the implant body. An keeper assembly for an implant that is fixed to an implant body embedded in a jawbone, (a) a head that is inclined with respect to a central axis of the implant body, and a central axis of the head A female screw provided; a cylindrical portion provided along a central axis of the implant body; and inserted into a central hole of the implant body; and a through hole extending from the cylindrical portion to a side surface of the head. An abutment, (b) a screw member having a male thread portion that penetrates the through hole and the cylindrical portion of the abutment and is screwed into the female thread portion of the implant body, and (c) a head portion of the abutment. A soft magnetic material having a recessed portion to be received and a female screw portion provided along a central axis so as to communicate with the concave portion and having a larger nominal diameter than the female screw portion of the abutment A keeper body comprising: (d) a small-diameter screw portion that is screwed with the female screw portion of the abutment; and a large-diameter screw portion that is screwed with the female screw portion of the keeper main body, the small-diameter screw portion and the large-diameter screw portion. A two-stage screw member having a taper portion formed between the two-stage screw member and the female screw portion of the abutment, and a small-diameter screw portion of the two-stage screw member. After the large-diameter screw portion of the two-stage screw member is screwed into the female screw portion, when the keeper body is rotated in the screwing direction, the keeper body is firmly fastened to the abutment by the two-stage screw member. When the two-stage screw member is screwed into the female screw portion of the abutment until the tapered portion engages with the upper end surface of the abutment, the two-stage screw member is accurately positioned in the axial direction. positioning can, before By screwing the screw member into the female screw portion of the implant body, an implant for keeper assembly, characterized by fixing the abutment to the implant body. 9. The implant keeper assembly according to claim 8 , wherein at least a part of the head portion of the abutment has a truncated cone shape, and an inner surface of the concave portion of the keeper body has a truncated cone shape portion of the abutment head portion. For implants, which have a complementary conical shape, so that when the keeper main body is fastened to the abutment, the frustoconical portion of the abutment head closely contacts the inner surface of the concave portion of the keeper main body. Keeper assembly. 10. The keeper assembly for an implant according to claim 8 , wherein at least a part of a side surface portion of the keeper main body is nut-shaped, and the keeper main body is screwed using a tool that engages with the nut-shaped side surface portion. An implant keeper assembly characterized by rotating in a direction. The keeper assembly for implants according to any one of claims 8 to 10 , wherein the abutment has a diameter-expanding portion connected to a lower end of the head, and an outer peripheral portion of an upper surface of the diameter-expanding portion is a keeper body. An keeper assembly for an implant, wherein the keeper assembly is in contact with a bottom edge portion, and a lower surface of the enlarged diameter portion is in contact with an upper end surface of the implant body.

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